Starting officially in the 2.3.0 release, OpenVPN supports IPv6 inside the tunnel, and can optionally be configured with IPv6 as a transport protocol for the tunneled data. There were some unofficial developer pâtches for the 2.2.x series that added partial IPv6 support (Debian in particular chose to integrate these pâtches into some of their builds.)

Providing IPv6 inside the tunnel

This section walks through providing IPv6 connectivity inside the tunnel; this will discuss a routed setup; a bridged (dev tap) setup is not recommended in general, and users doing so are presumably advanced enough to know what they're doing.

Requirements

A few things must be met in order to use IPv6:
•An existing and functional OpenVPN configuration (use the official howto if you don't yet have this.)
•A routed IPv6 network block that will reach the host configured as the OpenVPN server
•Both client and server must support IPv6; most modern systems these-days include this support already

Details: IPv6 routed block

In a routed setup, you cannot use your on-link network; you must use a unique routed network range, just like when routing with IPv4. Most ISPs should have a facility to obtain a routed block on request, or sometimes provided as part of DHCPv6-PD; these concepts are outside the scope of this document. Speak to your ISP or use other IPv6 learning resources for further information.

It is recommended to use a /64 for your OpenVPN subnet. While OpenVPN can happily use smaller networks (such as a /112) this is not compatible with the 2.2.x dev-pâtches that f.ex Debian uses. Thus a /64 is the preferred choice for an OpenVPN IPv6 allocation.

In this document, we'll assume you have the following from the OpenVPN server's viewpoint:
•The OpenVPN server has an IPv6 IP of 2001:db8:abc::100/64 on its LAN interface
•The following block is routed to the OpenVPN server host: 2001:db8:123::/64

Additional OpenVPN config

There are 2 ways to add IPv6 addressing and pool options to the server, similar to what OpenVPN supports for IPv4: using a helper-directive, and by expanding the helper-directive. The expansion is required if you do not wish to use the automatic values the helper-directive supplies. Clients who use --client or --pull will get the tun-ipv6 directive and addressing from the pool pushed as a result.

Config stanza using the helper

Add the following to a functioning OpenVPN config:
server-ipv6 2001:db8:123::/64

Config stanza with expanded directives​

Add the following to a functioning OpenVPN config: ​

tun-ipv6​

push tun-ipv6​

ifconfig-ipv6 2001:db8:123::1/64 2001:db8:123::0/64​

ifconfig-ipv6-pool 2001:db8:123::101/64
Pushing IPv6 routes

Pushing routes over the tunnel works much like it does in IPv4, but you use --push "route-ipv6 NETWORK/CIDR"

Using the addressing examples shown above, if you wanted to expose the server-side network of 2001:db8:abc::/64, you could use:
push "route-ipv6 2001:db8:abc::/64"

To redirect all Internet-bound traffic, use the current allocated public IP space like this:
push "route-ipv6 2000::/3"​

Checking if your Windows computer has the 5 GHz network band capabilityStep 1:Press the Windows key on your keyboard to access the Start screen. Type “cmd” until the search result appears under the Apps list. Select Command Prompt to open the application.

IMPORTANT: For Windows 8.1 you can right-click the Start button. Click Run then enter “cmd” on the field and press [Enter].NOTE: For touch-enabled computers, swipe from the right side of the screen to reveal the Charms bar with the system commands.QUICK TIP: The Search section will automatically appear once you type in any character from your keyboard.Step 2:On the Command Prompt window, enter “netsh wlan show drivers” then press [Enter].Step 3:Look for the Radio types supported section. If it says that the network adapter supports 802.11a or 802.11n network modes, this means that the computer that you are using has the 5 GHz network capability.In this example, the wireless adapter supports 802.11b, 802.11a, 802.11g, and 802.11n network modes. This means that the computer has the 5 GHz network band capability.Windows 7/VistaNOTE: A built-in wireless network adapter of a laptop computer is used for this example.Step 1:Click the Pearl button then enter “Device Manager” on the Search programs and files field. Click the Device Manager link once it appears on the search results. Step 2: On the Device Manager window, click Network adapters. Look for the name of your wireless adapter and check if it shows ABGN or AGN. In this example, the wireless adapter is Intel(R) Centrino(R) Ultimate-N 6300 AGN. This means that the computer has the 5 GHz network band capability.Windows XPIMPORTANT: A built-in wireless network adapter of a laptop computer is used for this example.Step 1:Click Start > Settings > Control Panel.Step 2:On the Control Panel window, double-click the System icon.Step 3:On the System Properties dialog box, click Hardware tab then click Device Manager.Step 4:On the Device Manager window, click Network Adapters. Look for the name of your wireless adapter and check if it shows ABGN or AGN.In this example, the wireless adapter is Intel® WiFi Link 5300 AGN. This means that the computer has the 5 GHz network band capability.NOTE: To identify Linksys dual-band routers and devices that support both 2.4 GHz and 5 GHz bands, click Please Login or Register to view links. For instructions on checking if your Mac computer is compatible with the 5 GHz frequency, click Please Login or Register to view links.Do you have a Linksys dual-band wireless router?Linksys dual-band routers support both 2.4 GHz and 5 GHz networks. You can use both networks simultaneously or use just one (1). Choosing between the two (2) frequencies will enhance the application you will be using on the wireless network. To know more about differentiating the 5 GHz and 2.4 GHz bands, click Please Login or Register to view links.

Some of My Old Tricks but Still Kicking and Helpful click nyo lang yung nasa baba nito.,